Specific entrustable professional activities for undergraduate medical internships: a method compatible with the academic curriculum.

BACKGROUND: Competency-based education has been considered the most important pedagogical trend in Medicine in the last two decades. In clinical contexts, competencies are implemented through Entrustable Professional Activities (EPAs) which are observable and measurable. The aim of this paper is to describe the methodology used in the design of educational tools to assess students´ competencies in clinical practice during their undergraduate internship (UI). In this paper, we present the construction of specific APROCs (Actividades Profesionales Confiables) in Surgery (S), Gynecology and Obstetrics (GO) and Family Medicine (FM) rotations with three levels of performance. METHODS: The study considered a mixed method exploratory type design, a qualitative phase followed by a quantitative validation exercise. In the first stage data was obtained from three rotations (FM, GO and S) through focus groups about real and expected activities of medical interns. Triangulation with other sources was made to construct benchmarks. In the second stage, narrative descriptions with the three levels were validated by professors who teach the different subjects using the Delphi technique. RESULTS: The results may be described both curricular and methodological wise. From the curricular point of view, APROCs were identified in three UI rotations within clinical contexts in Mexico City, benchmarks were developed by levels and validated by experts' consensus. In regard to methodological issues, this research contributed to the development of a strategy, following six steps, to build APROCs using mixed methods. CONCLUSIONS: Developing benchmarks provides a regular and standardized language that helps to evaluate student's performance and define educational strategies efficiently and accurately. The university academic program was aligned with APROCs in clinical contexts to assure the acquisition of competencies by students.

[The educational change in medical schools]. / Cambio educativo en las Facultades de Medicina.

This paper reports the reflections of a group of members of the University of Chile Faculty of Medicine, about the changes in teaching methods that medical schools should incorporate. In a complex scenario, not only new and better knowledge should be transmitted to students but also values, principles, critical reasoning and leadership, among others. In the first part, a proposal to understand this educational development in the context of complex universities, incorporating pedagogical skills and reviewing institutional leadership, is carried out. In the second part, the training of teaching physicians, as part of the changes, is extensively discussed. Physicians hired as academics in the University should have the opportunity to work mainly as teachers and be relieved of research obligations. For them, teaching should become a legitimate area of academic development.

Do you have COVID-19? How to increase the use of diagnostic and contact tracing apps.

Diagnostic and contact tracing apps are a needed weapon to contain contagion during a pandemic. We study how the content of the messages used to promote the apps influence adoption by running a survey experiment on approximately 23,000 Mexican adults. Respondents were randomly assigned to one of three different prompts, or a control condition, before stating their willingness to adopt a diagnostic app and contact tracing app. The prompt emphasizing government efforts to ensure data privacy, which has been one of the most common strategies, reduced willingness to adopt the apps by about 4 pp and 3 pp, respectively. An effective app promotion policy must understand individuals' reservations and be wary of unintended reactions to naïve reassurances.

Occupational health crossing borders part 2: Comparison of 18 occupational health systems across the globe.

BACKGROUND: Occupational health and safety (OHS) is considered one of the most important factors for a sustainable development; however, it is often considered a luxury by decision-makers. This article compares OHS systems of 18 countries at different stages of development. METHODS: In an international summer school, structure of the national OHS system, definition of occupational accidents and diseases, procedures for compensation claims, outcome (expressed as incidence of occupational accidents) and training opportunities were presented. RESULTS: National OHS systems ranged from non-existent to systems implemented almost 200 years ago. Priorities, incidence of occupational accidents and training opportunities varied. Common problems included the lack of OHS service for small enterprises and in rural areas. CONCLUSIONS: International training programs like this summer school might enhance the exchange about OHS opportunities around the globe and contribute to improved workers health.

A Phase II study of high-dose-rate afterloading brachytherapy as monotherapy for the treatment of localized prostate cancer.

PURPOSE: A Phase II dose escalation study has been undertaken to evaluate high-dose-rate brachytherapy (HDRBT) monotherapy for prostate cancer. METHODS AND MATERIALS: A total of 110 patients have been entered, all with locally advanced cancer. Three dose levels have been used; 34 Gy in four fractions, 36 Gy in four fractions, and 31.5 Gy in three fractions. These equate to 226Gy(1.5), 252Gy(1.5), and 252Gy(1.5), respectively. Thirty patients have received 34 Gy, 25 received 36 Gy, and 55 patients received 31.5 Gy. Acute and late toxicity was analyzed using the International Prostate Symptom Score, and urologic and rectal events were scored using the Radiation Therapy Oncology Group/Common Terminology Criteria scoring systems. RESULTS: Seven patients required urethral catheterization at 2 weeks; 3 receiving 34 Gy, 1 receiving 36 Gy, and 3 receiving 31.5 Gy. Only 3 patients remained catheterized at 12 weeks. Radiation Therapy Oncology Group 1 and 2 gastrointestinal toxicity at 2 weeks was seen in 61%, 68%, and 77%, respectively. Grade 3 bladder toxicity was seen in 2 patients at 6 months, 1 each from the 36 Gy and 31.5 Gy arms. One patient from the 31.5-Gy cohort reported Grade 2 bowel toxicity at 6 months. Prostate-specific antigen (PSA), stratified for androgen deprivation therapy (ADT) and no-ADT patients ranged from 16.1-22.9 microg/L and 11.1-12.5 microg/L, respectively. This fell at 12 months to 0.2-0.6 microg/L and 0.5-1.4 microg/L, respectively. No PSA relapses have yet been seen with a median follow-up of 30 months (34 Gy), 18 months (36 Gy), and 11.8 months (31.5 Gy). CONCLUSIONS: Early results suggest an excellent biochemical response with no differences seen in acute and late toxicity between doses of 34 Gy/four fractions, 36 Gy/four fractions, or 31.5 Gy/three fractions.

Exploring the FL-160-CRP gene family through sequence variability of the complement regulatory protein (CRP) expressed by the trypomastigote stage of Trypanosoma cruzi.

The complement regulatory protein (CRP) of Trypanosoma cruzi is a surface glycoprotein which confers to the infectious trypomastigote forms a protection against the lytic activity of the host complement. CRP belongs to the large family of the trans-sialidase-like proteins and its sequence is highly similar to those of the flagellar FL-160 and chronic exoantigen proteins, encoded by a multigene family. To further define the gene family encoding the CRP, we investigated the protein diversity among several strains of T. cruzi through the sequencing of trypomastigote transcripts, and used a phylogenetic analysis based on the multiple alignment of these proteins with the top scoring sequences detected by a database sequence homology search. Intrastrain variations in CRP sequences revealed the existence of several copies per strain. The interstrain variability of CRP was consistent with the genetic subdivisions of T. cruzi into lineages and discrete typing units. The phylogenetic analysis based on a 227 amino acid alignment of CRP sequences with the 200 putative proteins retrieved from the protein databases (including the sequences from the T. cruzi genome project) revealed that the CRP sequences clustered with the FL-160 proteins into a monophyletic group characterized by the presence of the 12 amino acid mimicry epitope that mimics nervous tissues. The phylogeny did not differentiate between the CRP and the FL-160 proteins. The identification of this group of CRP-like proteins and the high sequence similarity observed within it open up new prospects for the exploration of the localization, structure and function of these proteins and a better understanding of their involvement in key aspects of host-parasite interactions, such as the resistance to the complement. This work provides also information for the T. cruzi genome annotation of the trans-sialidase-like putative proteins.

DNA-labelled cytidine assay for the quantification of CAG repeats.

The sequencing procedure has been used to determine the size of the CAG repeat expansion for the diagnosis of genetic disorders. Likewise, standard polymerase chain reaction (PCR) and gel electrophoresis techniques are applied for screening large number of patients. The trinucleotide repeats (TNR) region amplification by means of the PCR procedure was initially performed using 32-P end-labelled primers and currently carried out with fluorescently end-labelled primers. The goal to obtain reliable TNR quantification assays, at low cost and short assay times, represents a challenge for the molecular diagnosis aimed at massive screening of affected populations. In the current work, we obtained preliminary results of a new methodology for the detection and size estimation of CAG expanded alleles. The assay was based on an indirect enzyme linked immunosorbent assay (ELISA) for quantifying the amount of labelled cytidines in DNA molecules. The label, 6-(p-bromobenzamido)caproyl radical, was introduced by the transamination and acylation reactions. A group of model sequences containing different numbers of CAG repeats, as well as the ATXN3 (ataxin 3) gene (from subjects suffering type 3 spinocerebellar ataxia SCA3) were used for assay standardization. The assay is simple, inexpensive, and easy to perform and differentiates distinct degrees of CAG expansions.

Plum (Prunus salicina) peel and pulp microparticles as natural antioxidant additives in breast chicken patties.

Fiber microparticles (MPCs) separately obtained from peel and pulp of Japanese plum residues contained co-extracted ß-carotene, lutein, and α- and γ-tocopherols, as well as polyphenols (cyanidins, quercetin derivatives, pentameric proanthocyanidins). Peel and pulp MPCs were then separately evaluated as natural antioxidant additives (2.0% w/w level) in raw breast chicken patty, susceptible to oxidation. Their effect on technological properties was also analyzed. MPCs reduced in 50% the formation of thiobarbituric acid reactive substances (TBARS) in raw patties during 10-days storage at 4.0°C. Ferric reducing power (FRAP) was 77-157% higher in MPCs-added patties, especially with peel MPCs, being then attributed to the antioxidants supplied by these MPCs. It can be also associated to the highest α- and γ-tocopherol levels found in the peel MPCs-added patties, which remained high after cooking as well. Also, higher pectin and low lignin contents of pulp MPCs determined greater hydration, stabilized the cyanidins and, hence, the red color transferred to raw patties, and increased springiness of cooked patties. Plum peel and pulp MPCs are efficient additives for chicken meat products.

[Level of teaching competence at the Undergraduate Medical Internship of UNAM's Faculty of Medicine]. / Nivel de competencia docente en el Internado Médico de Pregrado de la Facultad de Medicina de la UNAM.

BACKGROUND: There is no systematic evaluation of teaching performance in the clinical area at UNAM Faculty of Medicine. The study purpose is to assess the teaching competence level in the Undergraduate Medical Internship (UMI). METHODS: The paper describes the process of psychometric validity for the instrument designed to evaluate teaching competence in the UMI. This instrument was constructed from two previously developed instruments. The final version with 54 items in a Likert scale was studied with exploratory factorial analysis. Four dimensions were obtained: Solution of clinical problems, Psychopedagogy, Mentoring, and Evaluation. The instrument had a reliability of 0.994, with an explained variance of 77.75%. RESULTS: To evaluate the teaching competence level, we administered 844 questionnaires to a sample of students with a response rate of 89%. We obtained an overall global score of 89.4 ± 9.6 (mean ± SD). The dimension Solution of clinical problems was the one with a greater value, in contrast with the dimension of Evaluation, which had a lower score. CONCLUSION: The teachers of the UMI are considered educators with high level of teaching competence, according to the perceptions of the undergraduate internal doctors. The evaluation of teaching competence level is very important for institutions that look for the continuous professional development of its faculty.

Introducción: en la Facultad de Medicina de la Universidad Nacional Autónoma de México (UNAM) no hay una evaluación sistemática del desempeño docente del área clínica. El propósito de este estudio fue evaluar el nivel de competencia docente en el Internado Médico de Pregrado (IMP). Método: se describe el proceso de la validación psicométrica de un instrumento diseñado para evaluar la competencia docente en el IMP. El instrumento se construyó a partir de dos instrumentos previamente desarrollados y con base en el análisis factorial exploratorio de un instrumento con 54 reactivos y una escala tipo Likert, se obtuvieron cuatro dimensiones. El instrumento tuvo una confiabilidad de 0.994, con una varianza explicada de 77.75%. Resultados: para evaluar en nivel de competencia docente, se utilizaron 844 cuestionarios, lo que constituye la muestra de estudiantes, con una tasa de respuesta del 89%. Se obtuvo una media global de 89.4 ± 9.6 de desviación estándar. La Solución de problemas clínicos fue la que obtuvo mayor valoración, en contraste con la dimensión de Evaluación, que observó menor valoración. Conclusiones: los docentes del IMP son considerados educadores con alto nivel de competencia docente, según las percepciones de los médicos internos de pregrado. Se advierte cómo la evaluación de la competencia docente es indispensable en cualquier institución que busque el desarrollo profesional continuo de sus profesores.

Intermittent treatment with parathyroid hormone (PTH) as well as a non-peptide small molecule agonist of the PTH1 receptor inhibits adipocyte differentiation in human bone marrow stromal cells.

Whereas continuous PTH infusion increases bone resorption and bone loss, intermittent PTH treatment stimulates bone formation, in part, via reactivation of quiescent bone surfaces and reducing osteoblast apoptosis. We investigated the possibility that intermittent and continuous PTH treatment also differentially regulates osteogenic and adipocytic lineage commitment of bone marrow stromal progenitor/mesenchymal stem cells (MSC). The MSC were cultured under mildly adipogenic conditions in medium supplemented with dexamethasone, insulin, isobutyl-methylxanthine and troglitazone (DIIT), and treated with 50 nM human PTH(1-34) for either 1 h/day or continuously (PTH replenished every 48 h). After 6 days, cells treated with PTH for 1 h/day retained their normal fibroblastic appearance whereas those treated continuously adopted a polygonal, irregular morphology. After 12-18 days numerous lipid vacuole and oil red O-positive adipocytes had developed in cultures treated with DIIT alone, or with DIIT and continuous PTH. In contrast, adipocyte number was reduced and alkaline phosphatase staining increased in the cultures treated with DIIT and 1 h/day PTH, indicating suppression of adipogenesis and possible promotion of early osteoblastic differentiation. Furthermore, intermittent but not continuous PTH treatment suppressed markers of differentiated adipocytes such as mRNA expression of lipoprotein lipase and PPARgamma as well as glycerol 3-phosphate dehydrogenase activity. All of these effects of intermittent PTH were also produced by a 1 h/day treatment with AH3960 (30 microM), a small molecule, non-peptide agonist of the PTH1 receptor. AH3960, like PTH, activates both the cAMP and calcium signaling pathways. Treatment with the adenylyl cyclase activator forskolin for 1 h/day, mimicked the anti-adipogenic effect of intermittent PTH, whereas pretreatment with the protein kinase-A inhibitor H89 prior to intermittent PTH resulted in almost complete conversion to adipocytes. In contrast, the MAP kinase inhibitor PD 98059 failed to prevent the anti-adipocytic effect of intermittent PTH, suggesting that the inhibitory effect of PTH on adipocyte differentiation is predominantly cAMP-dependent. These results demonstrate a differential effect of PTH1 receptor agonists on the adipocytic commitment and differentiation of adult human bone marrow mesenchymal stem cells. This response may represent an additional mechanism that contributes to the overall bone anabolic action of intermittent PTH.

A framework for computational and experimental methods: identifying dimerization residues in CCR chemokine receptors.

Solving relevant biological problems requires answering complex questions. Addressing such questions traditionally implied the design of time-consuming experimental procedures which most of the time are not accessible to average-sized laboratories. The current trend is to move towards a multidisciplinary approach integrating both theoretical knowledge and experimental work. This combination creates a powerful tool for shedding light on biological problems. To illustrate this concept, we present here a descriptive example of where computational methods were shown to be a key aspect in detecting crucial players in an important biological problem: the dimerization of chemokine receptors. Using evolutionary based sequence analysis in combination with structural predictions two CCR5 residues were selected as important for dimerization and further validated experimentally. The experimental validation of computational procedures demonstrated here provides a wealth of valuable information not obtainable by any of the individual approaches alone.

Estructura organizacional del policlínico Julián Grimau para la respuesta médica ante emergencias químicas por amoníaco / Organizational structure of Julián Grimau polyclinic for medical response to chemical emergencies by ammonia

Introducción: El amoníaco constituye riesgo de emergencia química en el Policlínico Docente Julián Grimau del municipio Arroyo Naranjo, lo que hace necesario asumir una estructura organizacional que viabilice la respuesta médica frente a este tipo de eventos. Objetivo: Diseñar una propuesta de estructura organizacional del policlínico Julián Grimau para la respuesta médica ante emergencias químicas por amoníaco. Métodos: Se realizó una investigación en sistemas y servicios de salud, entre septiembre de 2017 y diciembre de 2018, en el Policlínico Docente Julián Grimau. Se analizaron documentos relacionados con las acciones médicas en las emergencias químicas en la atención primaria de salud. Se empleó el método sistémico estructural-funcional para diseñar la estructura organizacional, y el informante clave para su concreción. Resultados: Se propone una estructura organizacional de la respuesta médica a emergencias químicas por amoníaco en el Policlínico Docente Julián Grimau que se conformó por nueve áreas: punto de recepción (1), tratamiento especial (2), clasificación (3), tratamiento de urgencia al intoxicado grave (4), tratamiento de urgencia al intoxicado leve (5), aseguramiento al diagnóstico (6), aseguramiento médico material (7), el área de fallecidos (8) y asintomáticos (9). Conclusiones: La estructura organizacional de la respuesta médica a emergencias químicas por amoníaco en el Policlínico Docente Julián Grimau quedó conformada en áreas con sustento en los principios clínicos, evolutivos y de tratamiento del paciente intoxicado agudo, donde se aprovechan las potencialidades orgánicas y funcionales de la institución. Se caracteriza por ser sistémica, flexible, objetiva, participativa, oportuna, adecuada y selectiva(AU)

Introduction: At Julián Grimau Teaching Polyclinic in Arroyo Naranjo municipality, ammonia is a risk of chemical emergency. Hence, it is necessary for the medical response to these situations to implement an organizational structure. Objective: Design a proposal of organizational structure in Julián Grimau Polyclinic for the medical response to chemical emergency by ammonia. Methods: A research was carried out on health systems and services, from September 2017 to December 2018, in Julián Grimau Teaching Polyclinic. A documentary analysis related to medical actions in chemical emergencies was conducted in primary health care's level. In addition, the following methods were used: structural-functional system for the design of the organizational structure and the key informant for its concretion. Result: It is proposed an organizational structure of the medical response to chemical emergencies by ammonia in the Polyclinic, that was formed by nine areas: reception point (1), special treatment (2), classification (3), emergency treatment to severe poisoned patient (4), emergency treatment to slightly poisoned patient (5), logistics for the diagnosis (6), medical-material logistics (7), deceased´s area (8), and asymptomatic patients (9). Conclusions: The organizational structure of the medical response to chemical emergencies by ammonia in Julián Grimau Teaching Polyclinic was formed of areas secured by principles of clinical, evolutive and of acute poisoned patient´s treatment where the organic and functional potentials of the institution are seized. Hence, this proposal is flexible, objective, participatory, timely, adequate and selective(AU)

Automedicación con fármacos modificadores de pH gástrico: Estudio sistemático y metaanalítico

Objetivo: Determinar de la prevalencia de automedicación con fármacos modificadores de pH gástrico en América Latina. Material y métodos: Se realizó una búsqueda sistemática utilizando Google Scholar, PubMed, SciELO y repositorios de tesis iodo de enero de 2000 hasta agosto de 2021. Solo se incluyó estudios observacionales que contenían datos sobre automedicación y que contenían datos suficientes para calcular la prevalencia de automedicación, ya sea con número de pacientes o número de medicamentos. Se aplicó un modelo de efectos aleatorios para la construcción del diagrama de árbol en base al número de pacientes o número de medicamentos, con un intervalo de confianza (IC) del 95%. Resultados: Se incluyó 31 estudios, con un número total de 9 300 individuos encuestados y provenientes de 9 países (Argentina, Chile, Colombia, Ecuador, El Salvador, Honduras, México, Perú y Venezuela). La media de edad de los encuestados fue de 26,69 ± 11,15 años. Los estudios se realizaron en la población general, estudiantes universitarios y profesionales. La prevalencia combinada de automedicación con fármacos modificadores de pH gástrico fue del 13 % (IC de 95%: 8% a 18%, I =98%). Asimismo, los tres países con la mayor prevalencia de automedicación con fármacos modificadores de pH gástrico fueron: Colombia (53%), El Salvador (45%) y Perú (34%) Conclusión: La automedicación con necesario más estudios sobre la prevalencia y los factores asociados a este fenómeno.

Visión sistémica para respuesta médica a emergencias químicas por amoníaco del policlínico Julián Grimau / Systemic approach for medical response to chemical emergencies by ammonia in Julián Grimau polyclinic

Introducción: En el Policlínico Docente Julián Grimau, del municipio Arroyo Naranjo, el amoníaco constituye riesgo de emergencia química que puede afectar parte de la población que atiende. De ahí, que sea necesario para la respuesta médica ante estas situaciones, tener en cuenta las especificidades de la institución y su carácter sistémico. Objetivo: Proponer un sistema de respuesta médica ante emergencia química por amoníaco en el Policlínico Docente Julián Grimau. Métodos: Se realizó una investigación en sistemas y servicios de salud, entre septiembre de 2017 y diciembre de 2018, en el Policlínico Docente Julián Grimau. Se realizó un análisis documental relacionado con las acciones médicas en las emergencias químicas, en la atención primaria de salud. Se utilizaron, además, los métodos: sistémico estructural-funcional para el diseño del sistema, y el informante clave para su concreción. Resultados: Se plantearon premisas teórico prácticas y se diseñó el sistema de respuesta del policlínico, en su fase de alarma, que asumió dos subsistemas: el de urgencia, conformado por los componentes: recepción, tratamiento especial, clasificación y tratamiento de urgencia; y, el de aseguramiento, constituido por los componentes humano, material y diagnóstico. Conclusiones: La estructura sistémica organizacional de la respuesta médica ante emergencias químicas por amoníaco en el Policlínico Julián Grimau se sustenta en premisas teórico-prácticas propias que determinan la estructura holística institucional para establecer el proceso desde un enfoque sistémico-estructural-funcional. De ahí que el sistema propuesto, para la fase de alarma sea flexible, objetivo, participativo, oportuno, adecuado y selectivo(AU)

Introduction: At Julián Grimau Teaching Polyclinic in Arroyo Naranjo municipality, ammonia is a risk of chemical emergency that can affect part of the population that it serves to. Hence, it is necessary for the medical response to these situations to take into account the specificities of the institution and its systemic character. Objective: Propose a medical response system for chemical emergency by ammonia in Julián Grimau Teaching Polyclinic. Methods: A research was carried out on health systems and services, from September 2017 to December 2018, in Julián Grimau Teaching Polyclinic. A documentary analysis related to medical actions in chemical emergencies was conducted in primary health care's level. In addition, the following methods were used: structural-functional systemic for the design of the system, and the key informant for its concretion. Result: Practical- theoretical premises were stated and the polyclinic's response system was designed, in its alarm phase, which assumed two subsystems: the emergency one, formed by the components: reception, special treatment, classification and emergency treatment; and, the assurance one, consisting of human, material and diagnostic components. Conclusions: The organizational systemic structure of the medical response to chemical emergencies by ammonia in the Julián Grimau Polyclinic is based on its own theoretical-practical premises that determine the institutional holistic structure to establish the process from a systemic-structural-functional approach. Hence, the proposed system for the alarm phase is flexible, objective, participatory, timely, adequate and selective(AU)

Dynamic rheological measurements and drug release kinetics in swollen scleroglucan matrices.

The structure of scleroglucan gel matrices was characterized by dynamic rheological studies. The results were compared with the release kinetics of theophylline in analogous samples using a Franz diffusion cell, fitting the drug release data with a semi-empirical power law. Dynamic rheology gave information about the viscous and elastic components (loss and storage moduli, respectively) of the gel which could influence the drug-release profiles. Scleroglucan gels showed two structural transitions within the gel regime that coincided with changes in the release pattern. It was found that the introduction of 0.4% (w/w) of theophylline decreased the loss and storage moduli in the 2% (w/w) scleroglucan gels by 50%. The influence of the same wt.% theophylline in other gels was strongly dependent on the gel concentration. These results demonstrated the value of rheological studies to detect matrix structural changes produced by the inclusion of drugs which may modify the drug-release profile.

The Ras protein superfamily: evolutionary tree and role of conserved amino acids.

The Ras superfamily is a fascinating example of functional diversification in the context of a preserved structural framework and a prototypic GTP binding site. Thanks to the availability of complete genome sequences of species representing important evolutionary branch points, we have analyzed the composition and organization of this superfamily at a greater level than was previously possible. Phylogenetic analysis of gene families at the organism and sequence level revealed complex relationships between the evolution of this protein superfamily sequence and the acquisition of distinct cellular functions. Together with advances in computational methods and structural studies, the sequence information has helped to identify features important for the recognition of molecular partners and the functional specialization of different members of the Ras superfamily.

Tipificación mediante electroforesis de campos pulsantes de cepas de Streptococcus beta hemolíticos presentes en un brote de faringitis en niños / Typing by pulsed field gel electrophoresis of beta hemolytic Streptococcus strains present in a pharyngitis outbreak in children

Introducción: en infecciones por Streptococcus beta hemolíticos los del grupo A de Lancefield son el principal causante de faringitis en niños, y entre los no A los del Grupo C ocupan un lugar importante. Objetivo: tipificar molecularmente las cepas que participaron en un brote de faringitis en niños y demostrar la utilidad de la técnica de electroforesis de campos pulsantes en la identificación de las cepas circulantes. Métodos: se caracterizaron mediante electroforesis de campos pulsantes 12 aislados de Streptococcusbeta hemolíticos pertenecientes a niños atendidos en el Hospital Juan Manuel Márquez durante un brote de faringitis aguda en los meses de enero a marzo de 2008. Resultados: mediante el test de seroagrupamiento se encontró que 6 de los aislados, correspondiente al primer periodo del brote, eran Streptococcus del grupo C y los otros 6 aislados clasificaron como Streptococcuspyogenes, con una mayor presencia en la segunda etapa del brote. La subtipificación mediante la macrorrestriccion con SmaI y electroforesis de campos pulsantes mostró la existencia de dos poblaciones clonales consecutivas durante el brote. Conclusiones: los resultados obtenidos demuestran la utilidad que pudiera tener la subtipificación de aislados mediante electroforesis de campos pulsantes durante un brote o una reemergencia facilitando el control epidemiológico, la localización de la fuente y la toma de decisiones cuando esta fuera necesaria(AU)

Introduction: in the context of infection by beta hemolytic Streptococci, Lancefield group A is the main cause of pharyngitis in children, whereas Streptococci C play an important role in the non group A. Aims: the purpose of the study was to molecularly typify the strains involved in a pharyngitis outbreak in children, and show the usefulness of pulsed field gel electrophoresis technique for identification of circulating strains. Methods: twelve beta hemolytic Streptococcus isolates from children cared for at Juan Manual Márquez hospital were characterized by pulsed field gel electrophoresis during an acute pharyngitis outbreak from January to March 2008. Results: the serogrouping test found that six of the isolates, corresponding to the first stage of the outbreak, were group C Streptococci, whereas the other six classified as Streptococcus pyogenes, with a greater presence in the second stage. Subtyping by Sma I macrorestriction and pulsed field gel electrophoresis revealed the presence of two consecutive clonal populations during the outbreak. Conclusions: results show the potential usefulness of subtyping isolates with pulsed field gel electrophoresis during an outbreak or an instance of re-emergence, thus facilitating epidemiological control, location of the source, and decision making when required(AU)

Tipificación mediante electroforesis de campos pulsantes de cepas de Streptococcus beta hemolíticos presentes en un brote de faringitis en niños / Typing by pulsed field gel electrophoresis of beta hemolytic Streptococcus strains present in a pharyngitis outbreak in children

Introducción: en infecciones por Streptococcus beta hemolíticos los del grupo A de Lancefield son el principal causante de faringitis en niños, y entre los no A los del Grupo C ocupan un lugar importante.Objetivo: tipificar molecularmente las cepas que participaron en un brote de faringitis en niños y demostrar la utilidad de la técnica de electroforesis de campos pulsantes en la identificación de las cepas circulantes.Métodos: se caracterizaron mediante electroforesis de campos pulsantes 12 aislados de Streptococcusbeta hemolíticos pertenecientes a niños atendidos en el Hospital Juan Manuel Márquez durante un brote de faringitis aguda en los meses de enero a marzo de 2008.Resultados: mediante el test de seroagrupamiento se encontró que 6 de los aislados, correspondiente al primer periodo del brote, eran Streptococcus del grupo C y los otros 6 aislados clasificaron como Streptococcuspyogenes, con una mayor presencia en la segunda etapa del brote. La subtipificación mediante la macrorrestriccion con SmaI y electroforesis de campos pulsantes mostró la existencia de dos poblaciones clonales consecutivas durante el brote.Conclusiones: los resultados obtenidos demuestran la utilidad que pudiera tener la subtipificación de aislados mediante electroforesis de campos pulsantes durante un brote o una reemergencia facilitando el control epidemiológico, la localización de la fuente y la toma de decisiones cuando esta fuera necesaria(AU)

Creating reference datasets for systems biology applications using text mining.

High-throughput experimental techniques are generating large data collections with the aim of identifying novel entities involved in fundamental cellular processes as well as drawing a systematic picture of the relationships between individual components. Determining the accuracy of the resulting data and the selection of a subset of targets for more careful characterizations often requires relying on information provided by manually annotated data repositories. These repositories are incomplete and cover only a small fraction of the knowledge contained in the literature. We propose in this paper the use of text-mining technologies to extract, organize, and present information relevant for a particular biological topic. The aims of the resulting approach are (1) to enable topic-centric biological literature navigation, (2) to assist in the construction of manually revised data repositories, (3) to provide prioritization of biological entities for experimental studies, and (4) to enable human interpretation of large-scale experiments by providing direct links of bio-entities to relevant descriptions in the literature.

Homocysteine modifies fibrin clot deformability: another possible explanation of harm.

Several studies have associated elevated plasma homocysteine (Hcy) levels with higher risk of thrombosis. In order to evaluate possible changes in fibrin strength and deformability mediated by Hcy, the effect of the amino acid on plasma fibrin clot was studied, measuring the viscoelastic clots response as a function of Hcy concentration added to plasma (final concentrations: 0, 50, 100, 250 and 500 microM). Storage (G') and loss (G'') moduli were significantly higher than control at all Hcy concentrations evaluated in a dose-independent way (G'50 microM Hcy=254+/-10 Pa vs. 178 +/- 30 Pa, p=0.012; G''50 microM Hcy=32+/-1 Pa vs. 24 +/- 2 Pa, p=0.012). The tangent of the phase shift angles tan delta obtained from Hcy-clots with respect to control system proved to be unchanged (tan delta50 microM Hcy=0.130+/-0.007 Pa vs. 0.150 +/- 0.020 Pa, NS). Increases observed in G' and G'' values allowed us to conclude that Hcy action led to the stiffening of the clots formed in a dose independent way. The higher crosslinking of the fibrin network (higher G') contributed both to this structural behavior and to a higher compartmentalization and viscosity of the fluid phase (higher G'') of the gel. The lower deformability of the clots formed after Hcy addition was also detected through deformation sweep assays. These material's characteristics may lead to pathological behavior, increasing the chances of obstruction in the blood vessels.